The effect of solidification rate on micro-segregation in investment casting of IN738LC superalloy was studied. In Ni-based superalloys, the micro-segregation of solute atoms is formed due to limited diffusion during cast and solidification. The microstructure of cast Ni-based superalloys is largely divided into dendrite core of initial solidification and interdendrite of final solidification. In particular, mosaic shaped eutectic γ/γ’ and carbides are formed in the interdendrite of the final solidification region in some cases. The micro-segregation phenomena formed in regions of dendrite core and interdendrite including eutectic γ/γ’ and carbides were analyzed using OM, SEM/EDS and micro Vickers hardness. As a result of analysis, the lack of (Cr, W) and the accumulation of Ti were measured in the eutectic γ/γ’, and the accumulation of (Cr, Mo) and the lack of Ti were measured in the interdendrite between dendrite and eutectic. Carbides formed in interdendritic region were composed of (Ti, W, Mo, C). The segregation applied to each microstructure is mainly due to the formation of γ’ with Ni3(Al,Ti) composition. The Ni accumulation accompanied by Cr depletion, and the Ti accumulated in the eutectic region as a γ’ forming elements. The Mo tends to diffuse out from the dendrite core to the interdendrite, and the W diffuse out from the interdendrite to the dendrite core. Therefore, the accumulation of Mo in the interdendrite and the deficiency of W occur in the eutectic region located in the interdendrite. Heat treatment makes the degree of the micro-segregation decrease due to the diffusion during solid solution. This study could be applied to the heat treatment technology for the micro-segregation control in cast Ni-based superalloys.

A 20-year-old woman who had a main symptom of intermittent pain in both mandibular third molar visited our hospital. In CBCT findings, the #38, 48 teeth were located on the lingual side of the inferior alveolar nerve. In addition, a large stone about 12mm in length was observed in the right Wharton's duct in CBCT findings. Neck CT scan was performed and a large stone about 12mm in length was observed, and the accumulation of saliva in the rear of the stone was observed. The patient underwent sialolithotomy and #38, 48 tooth extraction through intraoral approach under general anesthesia. The removed stone was similar in shape and color to a tooth. The removed stone was markedly fragmented and composed of dentin and enamel-like tissue which showed lamellate arrangement in microscopic examination. Patient was presently symptom free after 10-months postoperatively.

The following study aims to estimate the configuration ratio of the ion compounds that identifies the cause of fine dust and ways to reduce it. In this study, the physical and chemical properties of fine particles in a tunnel and the configuration form of ionic composition were interpreted to establish reasonable measurement for air quality management. Seasonal measurements were performed by collecting samples from the Mia sageori subway station. Chemical Mass Balance (CMB) model was used to estimate the configuration ratio of ions in this study. The results showed that the test performed outside showed about 56.4% of total ion, with (NH4)2SO4, NH4NO3, CaCO3 and NaCl showing concentrations of 2.138 μg/m3, 1.957 μg/m3, 1.697 μg/m3 and 1.600 μg/m3, respectively, while the results indoor had CaCO3, NH4NO3, (NH4)2SO4 and NaCl showing concentrations of 2.272 μg/m3, 2.204 μg/m3, 1.656 μg/m3 and 1.342 μg/m3, respectively, about 65.1% of total ion. During the usage of tunnel, it was found that CaCO3, NH4NO3, (NH4)2SO4 and MgCO3 showed concentrations of 3.464 μg/m3, 1.732 μg/m3, 1.698 μg/m3 and 0.582 μg/m3, respectively, total ion of 70.2% was presented.

The objective of this research was to determine the effects of harvesting frequency and fertilization levels on botanical composition, dry matter yield, and forage feed compositions of Alpine grassland at 800 m altitude. This research lasted for three years at National Alpine Agricultural Research Institute in Pyeongchang with two harvesting frequency schedules (two and three times annually) and two levels of fertilizer application (conventional level of fertilizer at 280-200-240 kg/ha and a lower level of fertilizer at 200-200-200 kg/ha for N, P2O5, and K2O). Mixture combinations with seeding rate (kg/ha) were as follows: Orchardgrass 18, Tall fescue 9, Timothy 8, Kentucky bluegrass 3, and Ladino Clover 2. The gramineae ratio ranged from 93.2 to 95.3%. Therefore, gramineae forage was considered as the dominant plant in this experiment. No significant (p>0.05) difference was observed in forage dry matter yield between the two harvesting frequency treatments (two times at 9.8 ton/ha and three times at 8.6 ton/ha). However, forage dry matter yield in the two times of harvesting frequency tended to be greater than that in the three times of harvesting frequency. Significantly (p<0.05) higher forage dry matter yield in the standard fertilization level group than the lower fertilization level group (9.8 ton/ha vs. 8.7 ton/ha) was observed. However, there was no significant (p>0.05) difference in forage crude protein concentration between the two harvesting frequency treatment groups, although the concentration in the group with three times of harvesting frequency tended to be higher. In contrast, crude fiber concentration in the group with two times of harvesting frequency tended to be higher, although the difference was not statistically significant (p>0.05). Crude protein, ether extract, crude fiber, and organic matter concentrations were not significantly (p>0.05) different between the two groups with different fertilization levels. Based on these results, it was concluded that the group with two times of harvesting frequency with conventional fertilization level might be proper for obtaining better forage productivity for Alpine grassland at 800 m altitude.

복합재료 구성성분은 수 마이크로미터 수준의 크기를 가지고 있으므로 시험을 통한 정확한 물성 측정이 매우 어렵다. 그러므로 본 논문에서는 역해석을 이용하여 복합재료 구성성분의 열팽창계수를 예측할 수 있는 기법을 제안한다. 복합재료에 대한 등가 열팽창계수를 예측할 수 있는 Mori-Tanaka 기법과 결합된 역해석기법을 이용하면, 라미나 수준의 목적함수를 최소화함으로써 구성성분의 열팽창계수를 효율적으로 구할 수 있다. 본 연구에서 제안한 기법을 검증하기 위하여 다양한 섬유(glass fiber, P75, P100, M55J)에 대한 열팽창계수를 예측하고 이를 시험결과와 비교하였다. 또한 라미나와 기지 물성치에 대한 불확실성이 섬유 물성치 예측에 미치는 영향을 분석하였다.

Paralytic shellfish poison (PSP) occurrence and variation in the different bivalve species including oyster, Crassostrea gigas and mussel, Mytilus edulis in Jinhae bay Korea from January to December in 1997 were surveyed. And also compositional characteristics of PSP ingredients in the different bivalve species were investigated. PSP in shellfish was detected from late February and increased continuously until the middle of April in Jinhae bay. And after April PSP level had been decreased gradually and the toxicity was not detected by mouse bioassay in the early of June. Of the examined bivalve species, PSP content in the mussel exhibited the highest value and the PSP content in the mussel in the middle of April, PSP high season in Jinhae bay, was 6 times higher than that in the oyster. Gonyautoxin (GTX)1-4 group occupied 59.0-78.8% of whole PSP contents and identified as dominant ingredient in the examined bivalves except oyster. And it is also identified that the PSP toxicity in the tested species were derived from the GTX group. And the dominant ingredient of PSP in the oyster was carbamoyl-N-sulfo-llα- hydroxysaxitoxin sulfate(C1)(37.9%) and neosaxitoxin(neoSTX)(26.2%). But the toxicity of C1 in the tested oyster could be ignorable and most toxicity (80.0%) was derived from saxitoxin (STX) group.

질산염과 인산염의 농도가 다른 배지에서 Gymnodinium sanguineum과 Sketetonema costotum의 성장과 세포구성성분을 비교 분석하였다. 질산염은 0, 0.3, 0.6, 0.9, 1.2 mM, 인산염은 0, 15, 30, 45, 60μM을 각각 첨가한 배지에서 배양하였을 때, 저농도의 질산염 및 인산염 배지에서 G. sanguineum의 성장은 억제되었으나, S. costatum은 성장에 영향을 받지 않은 것으로 나타났다.

The effect of the role of alloyed components on the densification of two kind of high speed steel (mixed and prealloyed powder), which were sintered at 1403~ 1573 K for 7.2 ks in vacuum, was investigated. The results obtained were as follows. (1) Without the presence of Vanadium (V), the relative density of sintered compacts (Ds) could not reached the density of 100% regardless of the. elements in the compacts. (2) The addition of V up to 2 mass% did not result In the complete densification when the carbon content was fixed at 2% in the compact. (3) With the fixed amount of V of 7%, Ds decreased with the increase of the carbon content. (4) The addition of mixed fine powder to the prealloyed powder in the range of 20 to 40% provided the complete densification and carbide panicles of 1~2 through the solid phase sintering. (5) The V element played important role in controlling the complete or incomplete densification of the sintered compacts in the alloyed component because of its formation of stable oxide and carbide as well as the low equilibrium pressure of CO gas.

To find out the effects of phosphatic fertilizer application levels on the botanical composition, mineral contents and mineral nutrient deprivation of grasses and the chemical properties of soil, this expriment was arranged as a randomized complete block

초지관리용 2종 복합비료를 개발토자 시제품(N-P2O5-K2O-MgO-B2O3: 14-10-12-3-0.2)을 일반단비와 공시하여 비효를 비교검토하였다. 대상초지로는 새로 조성된 겉뿌림 혼파초지(orchardgrass, tall fescue, Kentucky bluegrass 및 ladino clover) 및 기존의 겉뿌림 단파초지(orchardgrass 우점초지)를 공시장소로하여 2년간 시험을 수행하였다. 1보에서는 토양

초지조성용 2종복합비료를 개발코자 시제품(N-P2O5-K2O-MgO-B2O3 : 8-25-7-3-0.2)을 일반단비와 공시하여 비효를 비교검사하였다. 겉뿌림 배양초지(orchardgrass, tall fescue, kentucky bluegrass 및 ladino clover)에서 2년간 수행하였으며 1보에서는 토양의 화학성 및 목장의 초기생육상, 본고에서는 수량성, 식생구성비율 및 목장의 영양성분에 미치는 영향을 검사한 결과는 다음과 같다

Background : Miscanthus sinensis is a diploid hybrid and a temperate, perennial, cross-pollinating grass used as bioenergy plant, biomass production and high quality cellulose and ethanol production. This study was to carried out to investigate the expression of MsCOMT gene and the variation of lignocellulosic component and phenolic compounds contents in transgenic plants. Methods and Results : Multiple bands were detected from the homologous region of the COMT gene in PCR analysis. In order to obtain more detailed results, putative transgenic lines were estimated by RT-PCR analysis to confirm the expression of mRNA. Also, analysis of the lignin, cellulose, hemicellulose, and phenolic compound contents of transgenic Miscanthus plants were performed. Total lignin content of transgenic plants was lower than that of the control plant due to reduced caffeic acid O-methyltransferase (COMT) gene expression related to lignin production. Cellulose and hemicellulose contents in transgenic plants were not increased. Variation in cellulose and hemicellulose contents had no correlation with variation in lignin content of transgenic plants. Conclusion : In conclusion, transgenic M. sinensis was obtained with down-regulated COMT gene. Lignin synthesis was decreased what offers possibility of crop modification for facilitated biofuel production.

This study investigated the changes in yields, antioxidant compounds, and antioxidant activities among 11 adzuki bean cultivars cultivated in a paddy field with somewhat poorly drained soil. The adzuki bean cultivars were cultivated in the paddy field from 2015 to 2016 in Milyang, Gyeongsangnam, Korea. Average soil moisture content was 16.5% in 2015 and 31.0% in 2016 at the experimental site during adzuki bean cultivation. As the soil moisture content increased, most of the adzuki bean cultivars showed deceases in stem height, first setting pod node, number of pods, 100 seed weight, and yield. Chungju-pat produced the greatest yields among the 11 cultivars in 2015 and 2016, whereas Hongeon had the smallest yields. Adzuki bean yields after paddy field cultivation was lower for all cultivars than for adzuki bean yields from the same cultivars after upland field cultivation. Chungju-pat and Chilbo-pat showed the smallest decreases in yields after paddy field cultivation, whereas Hongeon and Kumsil showed the greatest yield reductions. There were no significant differences in proximate composition. Some mineral components (P2O5, Ca, and Mg) were statistically different across cultivars. Chungju-pat had the highest Ca and Mg contents, but antioxidant components (polyphenol and flavonoids) and antioxidant activities (ABTS and DPPH) were highest in Saegil and lowest in Jungbu-pat. PCA and clustering analyses, based on the growth, yield, and antioxidant component measurements, performed to identify which variables contributed the most to separating adzuki bean cultivars or to grouping cultivars with similar characteristics. These analyses showed that the antioxidant components and antioxidant activities had the most influence on grouping cultivars together. Among the 11 cultivars, Saegil was statistically different from the other cultivars, but the other 10 cultivars were not significantly different under paddy field cultivation. Soil moisture content affected adzuki bean yield and antioxidant component contents. An increase in soil moisture led to a decrease in yield, but an increase in antioxidant components. These results provide information that will improve the selection of an appropriate adzuki bean cultivar for use in paddy fields.